The present invention refers to a turning device for graphic publishing products in a conveyor line and/or packaging machine that can be combined with a push conveyor for the advancement of products spaced out one after the other.
In packaging machines, or in conveyor lines of flat graphic and publishing products, namely sheets, signatures, magazines, brochures etc. made to advance one after the other, it must be possible to rotate and/or turnover these products, one at a time, to have both sides of the product being transported facing upwards at successive times.
This position is particularly useful when one or more additional sheets, or similar, generally known as inserts, must be combined with the graphic publishing product on both sides of the same product.
In fact, it is important that the inserts occupy a particular position or side of the product, depending on their importance and the desired type of impact on those buying the end product, with its relative inserts.
Various solutions are currently used to achieve this position.
An initial solution is that of adding a separate device at the end of the packaging machine or conveyor line, and placed in line with it, which turns the product over. Hence the turned product is then sent towards a second packaging machine or conveyor line which also adds each additional insert on a different side of the product before passing on to the packaging machine unit, which wraps it in a film of plastic material or a suitable paper cover.
This separate machine does not satisfy the need to put the required number of inserts on different sides, in addition to a basic product, and at high working speed. Furthermore, it involves the use of several lines and devices, which ties up considerable resources resulting in extra costs.
An additional solution put forward is that which is the subject of the European patent EP 819.637 of the same applicant, to which reference is made to better understand the need for such a device in a conveyor line and/or packaging machine.
Such a solution is accomplished with a grasping, rotation, 180xc2x0 turnover and belt guide unit which however sets the placing of the lengthwise lateral back of the publishing product in an opposite position in the two arrangements assumed before and after turning.
A further example of a solution is that shown in the patent EP 676.344 in which a swivel takes the incoming product in its pockets, turns it over and then releases it.
Such a solution requires specially shaped belts, both in the incoming conveyor line and the outgoing conveyor line from the swivel. Moreover, the swivel blades can hit against the pushers of the conveyor unit and hence the construction and setting up of such a device can prove complicated.
In addition, such a solution does not ensure the stability of the publishing product present in the pocket during rotation, especially when there are several overlapped products together. During rotation, the publishing product may even come out of the pocket, if rotation is at high speed. Hence a low speed is necessary. If there are several overlapped products, these are separated upon exit from the pocket and their feed is incorrect and disrupted on the exit belt.
One object of the present invention is to produce a device which solves the technical problems encountered previously.
In fact, the object of the present invention is to have a turning device which allows the fastest possible sheet insert feed into different sides of the graphic publishing product, within the same conveyor line or packaging machine, without having a different arrangement of the graphic product in relation to its lengthwise lateral back.
A further object of the present invention is to correctly accomplish this feed on the second side, even if a certain number of inserts have previously been fed into an initial product side.
Another object is to avoid any possible separation of the product and/or publishing products during the various loading, turning and unloading stages on the turning device.
These objects, according to the present invention, are reached by producing a turning device as detailed below.